1. Field of the Invention
The present invention relates to an organic light emitting diode (OLED) display device for visible ray communication, and more particularly, to an OLED display device for visible ray communication, whereby a visible ray signal is transmitted from the OLED display device, and another visible ray signal is received at the same time via a screen of the OLED display device, thereby enabling two-way wireless communication by using a visible ray signal.
2. Description of the Related Art
A visible ray communication method using a visible ray has several advantages over the conventional wireless communication method. A visible ray is transmitted or received only within a range that light reaches and is not transmitted through walls or doors, and thus, radio wave pollution is reduced. Accordingly, there is no need for additional radio-frequency authentication in the process of development of a visible ray communication device, making the development procedure thereof relatively easy. In addition, visible rays generated in a visible ray transmission/reception device may be used as an indoor illumination.
However, there are several problems in applying the visible ray communication method to an image display device.
Currently, a liquid crystal display (LCD) is widely used as a display device of, for example, a computer, a tablet computer, a TV, or a mobile device. A LCD uses a fluorescent lamp or a light emitting diode (LED) device as a backlight unit (BLU), and is configured such that visible rays generated in a light source as described above pass through a liquid crystal panel to be displayed in various colors and to be turned on and off. When a fluorescent lamp is used as a BLU in the LCD, light generated in a light source is not immediately turned on or off but the light is seen as being turned on or off via an operation of the liquid crystal panel while the light source is continuously in a switched-on state. Thus, the LCD using fluorescent lamp as a BLU is not appropriate as a device for transmitting a visible ray signal. Since an operating speed of a liquid crystal panel is limited, it is difficult to transmit a large amount of data by using a visible ray signal. When a LED is used as a BLU, visible ray communication may be performed by turning on or off the LED of the BLU; however, as the number of LED devices is relatively small compared to the number of pixels, it is difficult to control, for example, an area where the visible ray communication is conducted.